You want to share your desktop or just give some support directly to your friend or client in another country but don't have public ip! with
teamviewer you can make it.
This application is desktop application you just need install this application on your side an your friend/client side, and take her/his id and password and Instantly take control over a computer anywhere on the Internet, even through firewalls.
Teamviewer not just for desktop sharing, you can upload or download file from and to remote computer, share or show your software or just give some presentation with powerpoint or you just wanna chat with the remote like peer to peer.
For detail about this application you can find at
here